Inductor array in a single package

ABSTRACT

An inductor array comprising a magnetic body and a plurality of coils disposed in the magnetic body, wherein the magnetic body comprises a unitary portion that is disposed over and across the plurality of coils and extended into a space between each two adjacent coils of the plurality of coils.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims the benefit of U.S. Provisional Application Ser. No. 62/822,048 filed on Mar. 22, 2019, which is hereby incorporated by reference herein and made a part of the specification.

BACKGROUND OF THE INVENTION I. Field of the Invention

The invention relates to an inductor, in particular, to an inductor array in a single package.

II. Description of the Related Art

Conventionally, when multiple inductors are needed for an application, multiple inductors will be placed on a PCB board to meet the design requirement, which not only occupy a larger PCB board space but also make the assembly process slower by mounting the multiple inductors one by one.

Accordingly, there is demand for a better solution to solve these problems.

SUMMARY OF THE INVENTION

One objective is to provide an inductor array having multiple inductors in a single package to save PCB board space.

One objective is to provide an inductor array having multiple inductors encapsulated by a magnetic body for controlling the magnetic characteristic of the multiple inductors easily.

One objective is to provide an inductor array having multiple inductors in a single package to make the board assembly process faster and easier by mounting a single package containing multiple inductors on a PCB board.

One objective is to provide an inductor array having multiple inductors with different inductance in a single package to meet design requirements.

In one embodiment, an inductor array is disclosed, wherein the inductor array comprises: a plurality of coils; and a magnetic body, wherein the magnetic body encapsulates the plurality of coils, wherein at least one portion of the magnetic body has a unitary body that is disposed over and across the plurality of coils and extended into a space between two adjacent coils that is disposed over and across the plurality of coils and extended into a space between two adjacent coils.

In one embodiment, the plurality of coils are electrically isolated from each other inside the magnetic body.

In one embodiment, the plurality of coils are placed along a horizontal direction with the axis of each of the plurality of coils being substantially in a vertical direction.

In one embodiment, the entire magnetic body is a unitary magnetic body, wherein the unitary magnetic body encapsulates the plurality of coils and extends into a hollow space of each of the plurality of coils.

In one embodiment, the inductor array comprise four coils to form four power inductors, wherein two power inductors all have a first inductance, and the other two power inductors all have a second inductance that is different from the first inductance.

In one embodiment, the inductor array comprise four coils to form four power inductors, wherein two power inductors all have a first inductance, and the other two power inductors all have a second inductance that is different from the first inductance.

In one embodiment, the inductance is 0.24 uH.

In one embodiment, the first inductance is 0.11 uH and the second inductance is 0.24 uH.

In one embodiment, the magnetic body comprise a first T core and a second T core, wherein a first coil is wound around the pillar of the first T core and a second coil is wound around the pillar of the second T core, wherein the magnetic body comprises a unitary and magnetic molding body to encapsulate the first coil, the pillar of the first T core, the second coil and the pillar of the second T core.

In one embodiment, the first T core and the unitary and magnetic molding body are made of different magnetic materials.

In one embodiment, the first T core and the second T core are made of different magnetic materials.

In one embodiment, each of the first T core, the second T core and the unitary and magnetic molding body is made of a different magnetic material.

In one embodiment, each of the plurality of coils has a same inductance.

In one embodiment, the plurality of coils have different inductance.

In one embodiment, the coupling coefficient of adjacent inductors is within 0.02.

In one embodiment, the coupling coefficient of adjacent inductors is less 0.05.

In one embodiment, the inductor array comprise four coils to form four power inductors, wherein the four power inductors all have a same inductance.

In one embodiment, the magnetic body comprises at least one of the following: iron powder, alloy powder and ferrite.

In one embodiment, the plurality of coils are placed along a horizontal direction with the axis of each of the plurality of coils being substantially in said horizontal direction.

In one embodiment, each of the plurality of coils is formed by a conductive wire.

In one embodiment, each of the plurality of coils is formed by conductive patterns.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more fully understood by reading the subsequent description and examples with references made to the accompanying drawings, wherein:

FIG. 1A-1B each shows a top view of an inductor array according to one embodiment of present invention;

FIG. 1C-1E each shows a top view of an inductor array according to one embodiment of present invention with a distance between each two adjacent coils for controlling the coupling coefficient of the coils;

FIG. 1F shows a table of the relationship between the distance of two adjacent coils and the coupling coefficient of the two adjacent coils in accordance with an embodiment of the invention;

FIG. 2 shows a top view of an inductor array according to one embodiment of present invention;

FIG. 3A shows a schematic of the inductor array in accordance with an embodiment of the invention;

FIG. 3B shows a bottom view of the inductor array in accordance with an embodiment of the invention; and

FIG. 3C shows a diagram for connecting the inductor array with an IC in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

It is understood that the following disclosure provides many different embodiments, or examples, for implementing different features of the invention. Specific examples of devices and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features are formed between the first and second features, such that the first and second features are not in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

In one embodiment, as shown in FIG. 1A, an inductor array is disclosed, wherein the inductor array comprises: a plurality of coils 101, 102, 103, 104; and a magnetic body 100, wherein the magnetic body 100 encapsulates the plurality of coils 101, 102, 103, 104, wherein at least one portion 100 a of the magnetic body 100 has a unitary body that is disposed over and across the plurality of coils 101, 102, 103, 104 and extended into a space 105 a, 105 b, 105 c between each two adjacent coils of the plurality of coils 101, 102, 103, 104. Please note that there is no substrate inside the magnetic body to support the coils. In one embodiment, the bottom surface of each of the plurality of coils 101, 102, 103, 104 is in contact with the magnetic body 100.

In one embodiment, the plurality of coils 101, 102, 103, 104 are electrically isolated from each other inside the magnetic body.

In one embodiment, as shown in FIG. 1A, the plurality of coils 101, 102, 103, 104 are placed along a horizontal direction with the axis of each of the plurality of coils 101, 102, 103, 104 being substantially in a vertical direction.

In one embodiment, as shown in FIG. 1A, the entire magnetic body 100 is a unitary magnetic body, wherein the unitary magnetic body encapsulates the plurality of coils 101, 102, 103, 104 and extends into a hollow space of each of the plurality of coils 101, 102, 103, 104. In one embodiment, the bottom surface of each of the plurality of coils 101, 102, 103, 104 is in contact with the unitary magnetic body.

In one embodiment, as shown in FIG. 1A, the inductor array comprise four coils 101, 102, 103, 104 to form four power inductors, wherein two power inductors all have a first inductance, and the other two power inductors all have a second inductance that is different from the first inductance.

In one embodiment, as shown in FIG. 1B, the inductor array comprise four coils 101, 102, 103, 104 to form four power inductors, wherein two power inductors all have a first inductance, and the other two power inductors all have a second inductance that is different from the first inductance.

In one embodiment, each of the first inductance and the second inductance is 0.24 uH.

In one embodiment, the first inductance is 0.11 uH and the second inductance is 0.24 uH.

In one embodiment, as shown in FIG. 1C, FIG. 1D, FIG. 1E, the distance between adjacent coils can affect the coupling coefficient of the adjacent coils.

In one embodiment, the distance between adjacent coils is greater than 0.23 mm to allow the coupling coefficient of the adjacent inductors being less than 0.05, as shown in FIG. 1F.

In one embodiment, as shown in FIG. 2, the magnetic body 100 comprise a first T core 100 b and a second T core 100 c wherein a first coil 101 is wound around the pillar of the first T core 100 b and a second coil 102 is wound around the pillar of the second T core 100 c, wherein the magnetic body 100 comprises a unitary and magnetic molding body 101 a to encapsulate the first coil 101, the pillar of the first T core 100 b, the second coil 102 and the pillar of the second T core 100 c, wherein the unitary and magnetic molding body 101 a is disposed over and across the plurality of coils 101, 102 and extended into a space 105 a between two adjacent coils 101, 102.

In one embodiment, as shown in FIG. 2, the magnetic body 100 comprise a first T core 100 b, a second T core 100 c, a third T core 100 d and, a fourth T core 100 d, wherein a first coil 101 is wound around the pillar of the first T core 100 b, a second coil 102 is wound around the pillar of the second T core 100 c, a third coil 103 is wound around the pillar of the third T core 100 d, and a fourth coil 104 is wound around the pillar of the fourth T core 100 e, wherein the magnetic body 100 comprises a unitary and magnetic molding body 101 a to encapsulate the plurality of coils 101, 102, 103, 104, and the pillar of the first T core 100 b, the pillar of the second T core 100 c, the pillar of the third T core 100 d and the pillar of the fourth T core 100 e, wherein the unitary and magnetic molding body 101 a is disposed over and across the plurality of coils 101, 102, 103, 104 and extended into a space 105 a, 105 b, 105 c between each two adjacent coils of the plurality of coils 101, 102, 103, 104.

In one embodiment, the first T core 100 b and the unitary and magnetic molding body 100 a are made of different magnetic materials.

In one embodiment, the first T core 100 b and the second T core 100 c are made of different magnetic materials.

In one embodiment, each of the first T core 100 b, the second T core 100 c and the unitary and magnetic molding body 100 a is made of a different magnetic material.

In one embodiment, each of the first T core 100 b, the second T core 100 c, the third T core 100 d, the fourth T core 100 e and the unitary and magnetic molding body 100 a is made of a different magnetic material.

In one embodiment, each of the plurality of coils 101, 102, 103, 104 has a same inductance.

In one embodiment, the plurality of coils 101, 102, 103, 104 have different inductance.

In one embodiment, the inductor array comprise four coils to form four power inductors, wherein the four power inductors all have a same inductance.

In one embodiment, the magnetic body comprises at least one of the following: iron powder, alloy powder and ferrite.

In one embodiment, the plurality of coils are placed along a horizontal direction with the axis of each of the plurality of coils being substantially in said horizontal direction.

In one embodiment, each of the plurality of coils is formed by a conductive wire.

FIG. 3A shows a schematic of four inductors 101, 102, 103, 104 in a package 301, and each of the four inductors 101, 102, 103, 104 is electrically connected to corresponding two electrodes 101 a, 101 b, 102 a, 102 b, 103 a, 103 b, 104 a, 104 b.

FIG. 3B shows the electrodes of four inductors can be placed on the bottom surface of the package 301 having a width W and a length L, wherein each electrode can have a width A and a length B.

In one embodiment, each of the electrodes 101 a, 101 b, 102 a, 102 b, 103 a, 103 b, 104 a, 104 b is disposed on the bottom surface of the magnetic body.

In one embodiment, each of the electrodes 101 a, 101 b, 102 a, 102 b, 103 a, 103 b, 104 a, 104 b can be a surface-mount pad.

FIG. 3C shows a schematic of a package containing multiple inductors 101, 102, 103, 104 can be placed as a single component 301 for connecting with an IC 300, which not only reduces the board space to accommodate the multiple inductors but also makes the assembly process faster, compared with the conventional technology using multiple independent inductors.

From the foregoing, it will be appreciated that, although specific embodiments have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the disclosure. Furthermore, where an alternative is disclosed for a particular embodiment, this alternative may also apply to other embodiments even if not specifically stated. 

What is claimed is:
 1. An inductor array, comprising: a plurality of coils; and a magnetic body, wherein the magnetic body encapsulates the plurality of coils, wherein at least one portion of the magnetic body has a unitary body that is disposed over and across the plurality of coils and extended into a space between two adjacent coils.
 2. The inductor array according to claim 1, wherein the plurality of coils are electrically isolated from each other inside the magnetic body.
 3. The inductor array according to claim 1, wherein the plurality of coils are placed along a horizontal direction with the axis of each of the plurality of coils being substantially in a vertical direction.
 4. The inductor array according to claim 1, wherein the entire magnetic body is a unitary body, wherein the unitary body encapsulates the plurality of coils and extends into a hollow space of each of the plurality of coils.
 5. The inductor array according to claim 1, wherein the magnetic body comprise a first T core and a second T core, wherein a first coil is wound around the pillar of the first T core, and a second coil is wound around the pillar of the second T core, wherein the magnetic body comprises a unitary and magnetic molding body to encapsulate the first coil, the pillar of the first T core, the second coil and the pillar of the second T core.
 6. The inductor array according to claim 5, wherein the first T core and the unitary and the magnetic molding body are made of different magnetic materials.
 7. The inductor array according to claim 5, wherein the first T core and the second T core are made of different magnetic materials.
 8. The inductor array according to claim 5, wherein each of the first T core, the second T core and the unitary and magnetic molding body is made of a different magnetic material.
 9. The inductor array according to claim 1, wherein each of the plurality of coils has a same inductance.
 10. The inductor array according to claim 1, wherein the plurality of coils have different inductance.
 11. The inductor array according to claim 1, wherein the magnetic body comprise a first T core, a second T core, a third T core and a fourth T core, wherein a first coil is wound around the pillar of the first T core, a second coil is wound around the pillar of the second T core, a third coil is wound around the pillar of the third T core and a fourth coil is wound around the pillar of the fourth T core, wherein the magnetic body comprises a unitary and magnetic molding body to encapsulate the first coil, the pillar of the first T core, the second coil and the pillar of the second T core, the third coil, the pillar of the third T core, the fourth coil and the pillar of the fourth T core.
 12. The inductor array according to claim 1, wherein the distance between two adjacent coils is greater than 0.23 mm and the coupling coefficient of said two adjacent coils is less than 0.05.
 13. The inductor array according to claim 1, wherein each of the plurality of coils is electrically connected to two corresponding electrodes disposed over the bottom surface of the magnetic body.
 14. The inductor array according to claim 1, wherein the inductor array comprise four coils to form four power inductors, wherein the four power inductors have a same inductance.
 15. The inductor array according to claim 1, wherein the inductor array comprise four coils to form four power inductors, wherein two power inductors have a first inductance, and the other two power inductors have a second inductance that is different from the first inductance.
 16. The inductor array according to claim 14, wherein the inductance is 0.24 uH.
 17. The inductor array according to claim 15, wherein the first inductance is 0.11 uH and the second inductance is 0.24 uH.
 18. The inductor array according to claim 1, wherein the magnetic body comprises at least one of the following: iron powder, alloy powder and ferrite.
 19. The inductor array according to claim 1, wherein the plurality of coils are placed along a horizontal direction with the axis of each of the plurality of coils being substantially in said horizontal direction.
 20. The inductor array according to claim 1, wherein each of the plurality of coils is formed by a conductive wire. 